J. C. BrownAgricultural Research, Science and Education Administration, U.S. Department of Agriculture, Beltsville, MD 20705
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A. D. Draper
A. D. DraperAgricultural Research, Science and Education Administration, U.S. Department of Agriculture, Beltsville, MD 20705
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Contributor Notes
Received for publication March 14, 1979.
The cost of publishing this paper was defrayed in part by the payment of page charges. Under postal regulations, this paper must therefore be hereby marked advertisement solely to indicate this fact.